Feeding mechanism for extrusion machines



Nov. 21, 1933. s. c. BOND FEEDING MECHANISM FOR EXTRUSION MACHINES 2 Sheets-Sheet 1 Original Filed June 2, 1930 Nov. 21, 1933. s. c. BOND FEEDING MECHANISM FOR EXTRUSION MACHINES Original Filed June 2, 1930 2 Sheets-Sheet 2 SamueZ/ ifio z ff Patented Nov. 21, 1933 ATENT" OFFICE FEEDING MECHANISM FOR EXTRUSION MACHINES Samuel 0. Bond, Holly Oak, DeL, assignor to The Henry P. Scott Company, a corporation of Delaware, as trustee Application June 2, 1930, Serial No. 459,012 Renewed May 5, 1333 v5 Claims.

My invention relates to an improved feeding mechanism for extrusion machines, and has to do, more particularly, with the feeding of granular material such as comminuted cork into tubular molds or the like.

It is the primary object of my invention to provide a feeding mechanism for use with an extrusion machine which will maintain a more uniform rate of feeding than that heretofore obtained.

It is a further object of my invention to provide, in such a mechanism, means whereby the rate of feeding may be readily changed without requiring the adjustment of any moving parts and without interruption to continuousoperation. 7

A further object of my invention is to provide a simple, inexpensive, and trouble free device for accomplishing the above objects.

Further objects and objects relating to details and economies of operation will definitely appear from the detailed description to follow. In one instance, I accomplish the objects of my invention by the means described in the following specification. My invention is clearly pointed out in the appended claims. My apparatus illustrated, diagrammatically, in the accompanying drawing-s forming a part of this specification, in which:

Figure 1 is a front View of a preferred embodi- 'ment of my invention, parts being broken away;

Fig; 2 is a side view of the same apparatus, the righthand portion of the machine being shown in section;

Fig. 3 is a detail vertical sectional view through an extrusion tube and the hopper forming a part of the apparatus" shown in Fig. l, and

Fig. 4 is a perspective View of the hopper construction, theinclined rear wall thereof being omitted.

In the drawings, the same reference numerals refer to the same parts throughout the several views.

In the prior patent of W. G. Bond, No. 1,453,617, dated May 1, 1923, there is disclosed an Apparatus for manufacturing articles of comminuted cork on which the disclosed embodiment of my invention is an improvement, employing the same general construction. Although this invention is of especial value when embodied in a construction similar to that disclosed in such prior patent, it is not, in its broad aspect, so limited, being applicable to numerous analogous devices.

In the operation of the apparatus disclosed in said prior patent, considerable difficulty has at times been encountered, due to "bridging of the material across the hopper mouth, that is, the tendency of the material to be self supporting at this point and to resist uniform feeding into the breech portions of the tubes. Since, in the manufacture of articles of cork and similar materials by this process, uniformity of feed,- ing is absolutely essential, this problem has been of considerable importance and it is an object of this invention to solve it.

In general, my invention consists in the cornination, with a mechanism for ramming quanti-. ties of material into a tube comprising a reciprocating plunger, the end of which is successively projected into and retracted from the breech portion of the tube to force into the tube, material falling into the breech portion, of a hopper in which the material stored is not dumped directly into the breech, but is discharged upon the upper 7 surface of the plunger,.carried thereon toward the tube during the forward stroke, and caused to fall into the-breechv during the retraction of the plunger, to be rammed into the bore of the tube during the next forward stroke. This action 89 is made possibleoby the peculiar construction of the hopper which is provided with a materialretaining partition or gate, spaced at its lower edge from the breech portion of the tube'and from the exposed plunger surface; This partition or gate constitutes, in function, the front wall of the hopper, since the sump portion forward thereof contains substantially only that material car,- ried forward by the upper surface of the plunger. By adjustment between its lower edge and the top surface of the plunger, the quantity. of material carried forward by the plunger surface may be controlled, and the feed into the bore thus regulated. I

Referring to the numbered parts'of the drawings, the frame 10, which supports and houses the operating mechanism, is provided with one or more elongated troughs or sumps 11 through the sides and adjacent the bottom of which a plurality of extrusion tubes 12 extend. In an apparatus 1 for the molding of comminuted cork, agglomerated by means of a thermo-setting binder, these tubes extend outwardly from the trough for a considerable distance, as much as twenty to thirty inches and mounted thereabout are cooling chambers 13 and 15, and a heating chamber '14 through which cooling and heating fluids respectively circulate. The portion of each tube 12 lying intermediate the side walls of the trough 11 is no n tc ed to define, with the forward end of the plunger 1'7, when retracted, a breech 16 into which the material falls prior to being forced into the tube by the end of the plunger 1'7. Means are provided for reciprocating the plunger in the tubes and are preferably of the form disclosed in said prior Patent No. 1,453,617, comprising crossheads 1'7 on the plungers engaged with eccentrics mounted on shafting having bearings in the frame 10. A partition or gate 18 is supported in the sump by means of studs 19 set in the sump walls and lugs 20 attached to the gate. The lower edge of the gate is spaced from the plunger and from the tube, and by means of nuts 21 and 22 threaded upon the studs, adjustability of the spacing is provided. An inclined rear hopper wall 23 supports the major portion of the material, and by the use of a gate 18 of considerable height, constituting the front retaining wall, the necessity for any further wall structure is generally obviated. However, one such as disclosed in said prior patent, No. 1,453,617, may be employed if desired.

In operation, the gate 18 is adjusted to spacing in conformity with proper feeding and each plunger 17, during its forward stroke, draws, by reasonof friction with its exposed surface, a definite quantity of the material from the hopper defined by the walls 23, 18 and the rear portion of the trough 11. This measured quantity is that amount which will pass under the gate during the forward plunger stroke. Upon plunger retraction, this material falls into the breech of the tube to be rammed into the bore thereof by the succeeding forward stroke of the plunger. The process is continuous, each forward stroke of the plunger ramming into the tube the material carried by the last forward stroke, and each retraction of the plunger permitting the deposit in the breech of the material carried forward by the preceding forward stroke so as to be rammed into the tube 12 by the next forward stroke. In the use of a battery of tubes and a single gate having a straight lower edge, some material may be fed under the gate between the tubes, but no 45 tendency toward bridging occurs. Likewise, if the plunger stroke is such that in retracted position the plunger end is clear of the partition, a slight amount of material may be fed directly from the hopper into the tube, but also without occasioning any irregularity of feeding rate.

It will be observed that I have provided a very effective means for feeding comminuted cork and similar materials into a device having a bore, and one by which all tendency toward bridging is eliminated. Uniform feeding is accomplished and the rate may be readily changed while the apparatus is in operation, since the adjustment involves parts which are stationary and are remote from moving elements. While I have shown my invention embodied in an apparatus for manufacturing articles of cork, and in which it is of especial advantage, it is obvious that feeding devices constructed in accordance with my invention may be advantageously employed for use with other forms of apparatus having substantially horizontal bores into which such material as pulverized coal, sawdust, cement or a similar substance is to be fed.

I am aware that the apparatus herein disclosed may be changed considerably without departing from the spirit of my-invention. I, therefore, claim my invention broadly, as indicated by the appended claims.

What I claim is;

1. In a device having a member provided with a substantially horizontal bore through which material is to be rammed, a reciprocating plunger the forward end of which is successively projected into and retracted from said bore, defining, in its retracted position, the rear wall of the breech into which the material to be rammed is deposited, and a material-holding hopper having its mouth disposed above but rearwardly of said breech and resting its contents upon the exposed top surface of said plunger, the front wall of said hopper being spaced from the top surface of said plunger and from the front wall of said breech so that a quantity of material in the hopper mouth is carried upon said plunger surface beneath and past said front hopper wall during the forward stroke of the plunger, and upon retraction of the plunger, falls into said breech to be rammed into said bore by the next forward stroke of the plunger.

2. In a device having a member provided with a substantially horizontal bore through which material is to be rammed, a reciprocating plunger the forward end of which is successively projected into and retracted from said bore, defining, in its retracted position, the rear wall of the breech into which the material to be rammed is deposited, and a material-holding hopper having its mouth disposed above but rearwardly of said breech and resting its contents upon the exposed I top surface of said plunger, the front wall of 105 said hopper being spaced from the front wall of said breech and adjustably spaced from the top surface of said plunger so that a quantity of material in the hopper mouth is carried upon said plunger surface beneath and past said front 114) hopper wall during the forward stroke of the plunger, and upon retraction of the plunger, falls into said breech to be rammed into said bore by the next forward stroke of the plunger.

3. In a device having a member provided with 115 a substantially horizontal bore through which material is to be rammed, a reciprocating plunger, the forward end of which is successively projected into and retracted from said bore, defining, in its retracted position, the rear wall of the 120 breech into which the material to be rammed is deposited, and a material-holding hopper having its mouth disposed above but rearwardly of said breech and resting its contents upon the exposed top surface of said plunger, the front 5 wall of said hopper being spaced from the front wall of said breech and vertically movable to effect adjustable clearance of its lower edge with respect to the top surface of the plunger so that a quantity of material. in the hopper mouth is carried 13o upon said plunger surface beneath and past said front hopper wall during the forward stroke of the plunger, and upon retraction of the plunger, falls into said breech to be rammed into said bore by the next forward stroke of the plunger.

4. In a device having a member provided with a substantially horizontal bore through which material is to be rammed, a reciprocating plunger the forward end of which is successively projected into and retracted from said bore, defining, 140 in its retracted position, the rear wall of the breech into which the material to be rammed is deposited, and a material-holding hopper having its mouth disposed above but rearwardly of said breech and resting its contents upon the 14:5 exposed top surface of said plunger, the front wall of said hopper having the nature of a vertically adjustable gate supported at each side by nuts carried by upstanding threaded studs disposed at each side of the bore breech, said front hopper wall being thereby permanently spaced from the front wall of said breech and adjustably spaced from the top surface of said plunger so that a gauged amount of material is drawn forwardly from said hopper beneath and past the lower edge of said front wall during each forward stroke of the plunger, and upon each succeeding retraction of the plunger, falls into said breech, to be rammed into said bore by the next following forward stroke of the plunger.

5. An extrusion machine for cork composition and the like comprising a sump member having a plurality of alined apertures through its sides adjacent its bottom, extrusion tubes extending through the apertures of one side and having plunger guiding extensions extending through the alined apertures of the opposing side, each of said tubes being provided with a notch formed by cutting away its upper portion intermediate the sides of said sump member, a plunger in each tube, means for reciprocating said plungers so as to periodically project the forward ends of said plungers into the tubes proper beyond the forward edge of said notches, and periodically retract said plungers into said guide portions of said tubes with their forward ends disposed but part way across the notched tube portions, to define, with the plunger-cleared notched portions of the tubes, the tube breeches, and a materialholding hopper havingcits mouth disposed above but rearwardly of said breeches and resting its contents upon the notchexposed top surfaces of the plungers, the lower edge of the front wall of said hopper being spaced from the top surfaces of said plungers and disposed in substantially the plane defined by the rearwardmost limits of retraction of the forward ends of the several plungers so that a quantity of material in the hopper mouth is carried upon the notchexposed surface of each plunger beneath and past said front hopper wall during each of its forward strokes, and upon its retraction is allowed to fall into the tube breech defined by the notch and the forward end of the plunger, to be subsequently rammed into the tube proper by the next forward stroke of the plunger.

SAMUEL C. BOND.

(teammate or connection.

Patent No. 1536,2255. November 21, 933.

SAMUEL (I. BOND.

it is hereby certified that the above numbered patent was erroneously issued to "The Henry P. Scott Company, a corporation of Delaware, as Trustee," whereas said patent shouid have been issued to Bond Manufacturing Corporation, a corporation of Delaware, as assignee by mesne assignments, of the entire interest in said invention as shown by the records of assignments in this office; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent ()ffice.

Signed and sealed this 19th day of December, A. l). 1933,

Richard Spencer (Seal) Acting Commissioner of Patents. 

